David Orth

Clinical posts from members and guests of the Australasian Society for HIV, Viral Hepatitis and Sexual Health Medicine (ASHM) from various international medical and scientific conferences on HIV, AIDS, viral hepatitis, and sexual health.

Plenary 1 - Overview of Monoclonal Antibodies

The use of Monoclonal antibodies in HIV therapy seems to be close at hand. The first plenary of the conference focussed on this.

First potential compound identified in 2009 - today there are over 500 individual isolates. Initially investigated to better understand pathways to effective vaccination there seem to be clear applications for use in preventing HIV infection (PrEP) as well as suppressing viral replication.

Two attributes of MA are of interest

- Potency - dose required to neutralise the majority of viruses, and

-Breadth - the % of different HIV "strains" neutralised.

Currently no human data regarding passive protection from infection with monoclonal antibodies. Within a short time should have antibodies that bind four different sites. There is PK data and safety data from phase 1 trials. Animal data shows effectiveness.

The first trial in humans to assess the protectivity of MA will begin later in 2016. Based on earlier studies this will be a placebo controlled trial in high risk males in North America and high risk females in Africa.

It is likely that future compounds will be more potent and it is also likely that multiple compounds will need to be used at once to provide greater breadth.

There are a number of areas where monoclonal antibodies would have application clinically.

-Acute HIV infection to prevent or limit seeding of viral reservoirs

-to maintain long term viral suppression - given by injection every two -three months

- to reduce cell associated reservoirs.

Advantages of proposed compounds are

- they are distinctly different current medications and their resistance profiles will be different

- they have the potential to eliminate infected cells and may have a role in eradication

Limitations include

- they are unlicensed biologicals

- single compounds do not cover %100 of virus

In any case these exciting developments seem to indicate that we will have effective new tools within a relatively short time frame that will be effective at preventing infection as well as maintaining viral suppression. They may also have a role in assisting with eradication of the HIV infected cells.